Bison Osteology

Although we will be working with the bones of several species in the class, we'll often use the bison skeleton as a basic frame of reference since your instructor is somewhat bisonocentric and many of our research project will involve analysis of bison bone assemblages from Plains archaeological sites. Once you know the basic bison bones, you've gotten a lot of the groundwork done for study of all other mammalian skeletons.

During class and in the labs we will be giving you a number of mnemonics to help you identify and remember the bones (e.g., thoracic centra look like Mickey Mouse; a talus is a swimming duck; third phalanges are shaped like a bird's beak). Two of these mnemonics that have the most general applicability are:

the medial surface of limb bones is broader and more massive than that lateral. This is especially useful in identifying the side of the bone..
the bison skeleton is "aerodynamic" -- think about the way bones would interrupt air-flow and you'll often have a good idea of which is the cranial (toward the front) and caudal (toward the back) of the animal. For example, the cranial surface of the centra of nearly all vertebrae (atlas is the exception) are convex while caudal surfaces are concave. Air would flow across the convex cranial surface smoothly, but be push against the concave caudal surface. Or, the cranial border of the scapula is shaped like the leading edge of an airplane wing.

Includes the cranium, the mandible, teeth, and the hyoids. Note that the term skull means that both the cranium and mandible are present. A mandible from a younger animal with the deciduous premolars is also shown.

Axial Skeleton

The vertebrae, ribs, and sternum. Only the ribs are paired elements (left and right side) -- the vertebrae and sternabrea are not paired

Appendicular Skeleton

The limbs -- limbs are paired elements (one on the left and one on the right).